Bending techniques that avoid rippling

Tubing can be bent to consistent radii with no distortion because of its symmetrical nature, but several things must be taken into account in order to avoid rippling. In this post we will explain how it occurs in bending and tube ring rolling, and what material should be used to avoid it. Once the material has been decided on, the right machine, methods, and tools must be used to avoid distortion.

Multiform Tubes use techniques such as looking at the outside and inside bend radii, which helps identify the best tooling and machine for successfully bending. What method offers the most support is heat reduction, rotary draw/push operation, or using a die which matches the size and shape of the tubing used.

When bending a tube to a radius 8 or larger than the diameter should be able to withstand being bent on a rolling machine. The wall should be thick enough for stability under opposing tensile and compressive forces.

Springback can occur resulting in radial growth when bending. This is accounted for by having tubes marginally over bent or to a smaller radius than the design print requires depending on what material is used and how small the radius is. Steels with high tensile and yield strengths need rolling to a tighter radius than the design requirements to achieve the true design. This must be done because straining the material will force it to hold shape. Most steel grades and sizes don’t need severe over bending to achieve the expected results.

It is always a good idea to consult with a company like ourselves, Multiform Tubes. We will help determine the best techniques and material to achieve the desired curvature. We are specialists in bending, manipulation and tube ring rolling, with a high standard of knowledge so you receive the best results every time.

If you have any questions for us, or would like to arrange a service, please get in touch.